Rail bonding apparatus



c. A. CADWELL 2,276,823

RAIL BONDING APPARATUS March 17, 1942.

Filed Dec. 15, 1940 4 Sheets-Sheet l g g g hum IN VENTOR.

CHARLES A CADWE LL M, 5M 1) 9M ATTORNEYd March 17, 1942. c. A. CADWELL2,276,823

RAIL BONDING APPARATUS Filed Dec. 15, 1940 4 Sheets- -Sheet 2 TIE-JO 4334 INVENTOR.

38 CHARLES A.CADWELL ATTORNEYS March 17, 1942. c c w 2,276,823

RAIL BONDING APPARATUS I Fi led Dec. 15, 1940 4 Sheets-Sheet 3 nu munINVENTOR.

26 CHARLES A. CADWELL cm, (MK/L 19 ATTORNEYS March 17, 1942. c. A.CADWELL 2,276,823

RAIL BONDING APPARATUS Filed Dec. 15, 1940 4 Sheets-Sheet 4 he. l9.

INVENTOR.

CHARLES A.CADWELL miaww ATTOR N EYS Patented Mar. 17, 1942 UNITED STATESPATENT OFFICE 2,276,823 RAIL BONDING APPARATUS Charles A. Cadwell,Cleveland, Ohio, assignor to The Electric Railway" Improvement Company,Cleveland, Ohio, a corporation of Ohio Application December 13, 1940,Serial No. 370,015 21 Claims. ,.(,Cl. 22-116) This invention relates asindicated to rail bonding apparatus, and more particularly to a form ofapparatus designed for attaching railway signal conductors by castwelding the ends of such This application is a conductors to the rails.continuation in part of my co-pending application Serial No. 243,351,filed December 1, 1938, now Patent 2,262,755, dated Nov. 18, 1941 andalso a continuation in part of application Serial No. 107,051, filedOctober 22, 1936, now Patent 2,238,926, dated Apr. 22, 1941.

Various means have been suggested by workers in the art for cast weldingthe ends of rail bonds to rails but such means have not generally beenconducive to rapid attachment of the bonds nor uniform in the resultsafforded. As disclosed in my co-pending applications Serial No. 245,954,filed December 15, 1938 now Patent 2,229,045, dated Jan. 21, 1941, and'Serial No. 243,394, filed December 1, 1938, I have developed a newmethod of attaching rail bonds involving the use of an exothermicreaction for the production of the necessary weld metal, and it is aparticular object of the present invention to provide apparatus adaptedfor use in connection with such method.

It is a further object of this invention to provide apparatus which willbe substantially selfadjusting and will properly position the ends ofthe conductor for attachment to the rail. I

Another object is to provide such apparatus which will be readilyremovable from the rail head after the terminal has been cast withoutinterference from any excess metal and slag which may be solidified inthe sprue leading to the mold cavity in which the terminal is cast.

A further object of this invention is to provide means whereby a streamof molten metal may be conducted to a mold cavity in which the terminalis to be cast in a manner best calculated to form a sound terminal andwithout injury to the rail.

Other objects of this invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention,then, consists of the means hereinafter fully described and particularlypointed. out in the claims, the annexed drawing and the followingdescription setting forth in detail certain means and one mode ofcarrying out the invention, such disclosed means and mode illustrating,however, but one of various ways in which the principle of the inventionmay be used.

In said annexed drawings:

Fig. 1 is a top plan view of one embodiment of the apparatus of myinvention indicating the manner in which the same is positioned on therail head which is shown in outline;

Fig. 2 is aside elevational view of the same apparatus with the railshown in cross section;

Fig. 3 is a sectional view taken along the line 33 on Fig. 1, showingthe arrangement of parts in position for casting of the terminal; I

Fig. 4 is a similar sectional view but showing the parts arranged forremoval of the apparatus from the rail head after casting of theterminal;

Fig. 5 is an enlarged horizontal sectional view taken through the moldcavity of the mold block showing the manner in which the conductor endis positioned therein;

Fig. 6 is an enlarged vertical sectional view through the mold cavity;

Fig. 7 is an elevational view of the apparatus taken along the line 11on Fig. 1;

Fig. 8 is a top plan view of another embodiment of my invention showinga form of apparatus especially useful in constricted places, as adjacentswitches, crossings, and the like;

Fig. 9 is a side elevational view of the apparatus of Fi 8;

Fig. 10 is an end view of such apparatus showing the clamping means inrail engaging position;

Fig. 11 is a view similar to Fig. 10 but showing the clamping means inelevated position to permit withdrawal of the mold from the face of therail;

Fig. 12 is a sectional view taken along the line l2-l2 onFig.8;

Fig. 13 is a fragmentary top view showing the mold supporting meanstaken along line [3-13 on Fig. 12; v

Fig. 14 is a sectional view through the mold cavity taken along the linel4-|4 on Fig. 12;

Fig. 15 is a perspective view of a cast terminal prior to removal of theoverflow lug;

Fig. 16 is a somewhat diagrammatic sectional view taken along the lineIii-l6 on Fig. 12, showing the flow of molten metal down the spruepassage;

Fig. 17 is a diagrammatic view illustrating the manner in which thestream. of molten metal is spread or fanned out;

Fig. 18 is a fragmentary sectional view showing the construction of themeans whereby the movable block is attached to the mold block proper; 1

F 19 is a top view similar to Fig. 8 but illustrating another type 01'crucible;

Fig. 20 is an end View of the assembly including such crucible;

Fig. 21 is a side elevational view of such assembly with the crucible incross-section;

Fig. 22 is a sectional view of the crucible opened to permit removal ofslag; and

Fig. 23 is an elevational view in cross-section showing such cruciblemounted on a mold block in the manner illustrated in Figs. 1-7.

Referring now more particularly to the drawings, and especially Figs. 1and 2, one embodiment of the apparatus of this invention comprises acrucible block I attached by means of a hinge 2 to a mold block 3. Thismold block is supported in an iron mount 4 pivotally carried on the endof a screw member 5 which is threaded in one end of a curved frame piece6 spanning the rail head I and engaging the side of the rail headopposite to that contacted by the mold block. An adjustment is providedin the form of a screw 8 by which such frame piece may be adapted tovaryingiwidths of rail head so as to properly position the mold block.iUndue rotation of such block on itspivotal mount is prevented by meansof across brace 9, one end of which loosely encircles frame piece 6. Themold block is thus enabled to adapt itself to slight differences ininclination of the rail heads.

The crucible block, generally of graphite, is hollowed out to form thecrucible I!) which is adapted to communicate by means of a hole ,H atits bottom with the sprue opening l2 which is hollowed in the face ofthe mold block 3. Such sprue opening communicates with the mold cavity13 in which the bond terminal is to be cast. When metallic copperproduced by an exothermic reaction is to be employed, for example,in'the casting of the terminal, such mold cavity may desirably beextended to form a further inner cavity l4 separable from the moldcavity proper l3 by means of a graphite disk t5 perforatedv in itscenter to provide a small opening It. A small hole ll leads from thefurther extremity of such inner cavity to the outer air in a hollowspace beneath the iron mount 4. These particulars of the mold cavity arebestshown in Figs. 5 and 6 which also indicate the position of theconductor end It in the mold cavity, the body of the-conductor [9adjacent such end being enclosed in a metal sleeve 20. The railcontacting face of the mold block is suitably hollowed to form a smallercavity 2| extending from the mold cavity to an adjacent end of the moldblock and adapted to closely fit the sleeve portion of the bond.

Between the top of the rail head and the crucible block l is a movablemember 22 pivotally or swingably attached to such mold block by means ofa resilient member in the form of a spring 23. As best shown in Fig. 4',this movable member, which is also of graphite, may be slid to the uppersurface of the mold block after first swinging back the crucible blockupon its hinge. As a result of the above-described construction, it willbe seen that the sprue passage 12, in addition to having its lowerportion open to the rail contacting face of the mold b lock,'can befurther opened or exposed by swinging orsliding the movable member orgate 22 from the position shown in Fig. 3 to that shown in Fig. 4,thereby facilitating removal of the mold from the rail upon completionof the welding operation after which any excess metal or slag which'hassolidified in the sprue may be conveniently removed from the main bodyof the bond-terminal by ablow of a chisel. i I

When employing an exothermic charge of the type disclosed in myco-pending application Serial No. 245,954, a metal slug or gate isplaced in the bottom of the crucible H] and such exothermic charge andignition material placed in the crucible. Upon ignition of the chargesuch metal gate is melted and the highly heated welding metal passesthrough sprue l2 into the mold cavity l3. When an inner cavity, such asM, is provided, a portion of the molten metal will pass through theopening [5 in the graphite disk to fill such inner cavity. This has theeffect of permitting the first portion of the charge to sufficientlyheat the face of the rail head to ensure that it is properly interfusedwith such face. The mass of the thin graphite disk [5 is so small that atem perature approximately equal to that of the inflow metal isinstantly acquired by the disk, and due. to the position of the hole inthe disk relative to the end N3 of the conductor the high velocity or"the stream of metal flowing against and through the disk carries awayfrom about the end of the conductor what would otherwise be relativelycold shot metal lying against the strands and permits fresh hot metal tofill the interstices between and join with the strands, and so producethe desired weld. The small opening l1 permits the escape of the air inthe inner chamber and also the escape of gases given off by the moltenweld metal and which would otherwise tend to render such metal spongyupon solidification.

The apparatus of this invention, and particularly the mold abovedescribed, has been'found to be particularly advantageous when employedin the cast welding of stranded copper conductors to steel rails, suchprocess having previouslybeen attended with considerable difiiculty inobtaining a terminal which was mechanically sound without injury to therail head due to local overheating. Upon removal of the mold block inthe manner above indicated, that part of the weld metal which hassolidified in the inner overflow cavity may be readily removed by asharp blow of a hammer since it is entirely separated from the main bodyof the weld by the graphite disk except for the slight amount of metalcontained in the hole in said disk. A smooth bond terminal of minimumsize is thus obtained.

The inner wall of the sprue passage l2 will desirably be somewhatinclined towards the face of the rail head so that the molten metalpassing therethrough will be caused to impinge on the rail head at adistinct angle. It has been found that if superheated copper from anexothermic reaction be caused to impinge on a steel surface at an anglesubstantially normal to such surface, there is a distinct danger, ofoverheating the steel and reducing the ability of the latter to sustainthe stresses'to which a rail is subjected in use. This is particularlytrue when the stream of metal is relatively narrow and strikes only asmall localized area of the rail head. On the other hand, if the streamof molten copper is caused to enter themold cavity in such a manner thatit fails to impinge on the steel surface at all, insufilcientinterfusion of the two metals is likely to result. The mold of thisinvention has therefore been constructed so as to cause the moltencopper to impinge at a slight angle on the face of the rail head.

This mold assembly comprising complementary elements of refractorymaterial which cooperate to define the sprue opening leading upward fromthe main mold cavity permits of rapid removal after casting of theterminal without damage to the apparatus. The removal of slag from thesprue and cleaning of the interior are also greatly facilitated.

Referring now to Figs. 8 to 18 inclusive and particularly Figs. 8, 9 and12, another embodiment of my invention is here illustrated havingcertain elements further modified as will be explained below. Thisapparatus comprises a mold block 24 and a tubular supporting frame 25operative to hold such mold block in clamping engagement with the faceof the rail. The lower portion of such block will desirably be encasedin a metal shell 26 which may be fitted or preferably cast in place,such shell serving to prevent possible fracture of the graphite blockduring use. A pin 21 passes through the block and the upper ,portion ofsuch shell, supporting the same in clevis 28 which in turn is carried onthe end of threaded rod 29 passing through a boss 30 in the frame 25. Anut 3| is employed to secure such rod in.place and also secure the endof leaf spring 32 which is operative to bear on therear of the block 24.A handle 33 attached to frame 25 is provided for ready manipulation ofthe device.

Means for clamping the mold to the rail comprise angular extensions 34and 35 of frame 25 pivotally mounted in such frame at joints 3Sand 31and overlapping members38 and 39- slidably held in the respective endsof such extensions. A rod 40 having a high pitched thread is inserted insimilarly threaded holes in the overlapping portions of such memberscarrying a loosely pivotally mounted clamping foot 4| at its inner endand having an unbalanced handle 42 at its outer end. Upon depressing rod40 as'rbest shown in Figs. 9 and 10 the foot 4| is brought into positionto engage the side of the rail head 43 and when,

it is desired to remove the apparatus from the a rail such clampingmeans is elevated as shown in Fig. 11. (Also, see Fig. 12 where the dashline A position is that of Fig.'11 and the solid line B positioncorresponds to Fig. 10.) The mold may then be withdrawn from the face ofthe rail and the apparatus moved. It will be apparent from the foregoingthat such apparatus may be employed in very constricted places since,when it is desired to remove the same, only the mold block is below thelevel of the rail head.

The rail engaging face of mold block 24 is hollowed out to provide themold cavity 44 in which the terminal is cast, with a smaller cavity 45communicating with an adjacent end of the mold block and adapted to fitthe body of the conductor 46 as shown in Fig. 14. When employing moltencopper from an exothermic reaction as the welding metal it is' desirableto provide an overflow cavity 41 communicating with the main mold cavity44 except in the case of the smallest sizes of signal bonds. Thefunction of such overflow cavity is explained below. A sprue passage 48is also provided leading upwardly from mold cavity 44, such passagebeingpartly in the face of block 24 and partly formed by the complementaryhollow 49 in the inner face of movable block 5|]. Springs 5| and 52 holdsuch movable block in close resilient engagement with the face of block24 and permit such movable block to be slid up out of the way to theposition illustrated in Figs. 11 and 12. Tubular metal shields 53 and 54enclose and protect such springs, particularly from damage by moltenmetal, such shields being slidably mounted on pins such as 55 (see Fig.'18).

A crucible 56 is provided for use in cooperation with the abovedescribed mold, such crucible being vertically divided into twohalves'joined by a hinge 51. A snap spring 58 serves .as a catch to keepthe two halves in cooperative. engagement. The inner wall 59 of thecrucible tapers as shown in Fig. 12 to aid in avoiding spattering duringthe exothermic reaction. As a result, removal of the shell of slagusually left therein would be diflicult if it were not for the fact thatthe crucible is thus split. A short sprue or tap hole 60 is provided inthe bottom of the crucible which is-closed in use with a metal gatewhich will be melted by the heat of the reaction. An arch or bridge 6|supports the crucible in position so that the stream of molten metaldropping from tap hole 60 will fall into the sprue passage formed by thehollow 49 in movable block 56. The arch is carried on semi-cylindricalfeet 62 and 63 resting on frame 25 and positioned thereon by engagementof small pins 64 and 65 in holes through such feet. The heads of thesepins are adapted to rest on the head of the rail.

Referring now particularly to Fig. 12, the operation of this form ofapparatus may be explained as follows: The frame is rested on the railhead and the end of the conductor cable, suitably encased in a sleeve65, is positioned in the mold cavity as illustrated in Fig. 14. Rod 40is dei pressed and rotated to bring foot 4| into clamping engagementwith the side of therail head opposite to that engaged by the mold, asshown in solid line in Fig. 12, thereby firmly holding the conductor inplace. Spring 32 permits the slight automatic adjustment necessary inorder that the mold may accommodate itself to minor differences ininclination of the side of the rail head. Movable block 58 is positionedas shown in solid line in Fig. 12. In the meantime crucible 55 has beencharged with the material for producing the exothermic reaction, a metalgate closing the tap hole, and supporting feet 62 and 63 are properlyregistered on frame 25. Upon ignition of the charge the gate is meltedand the stream of molten metal drops into'sprue passage 49, 48, andthence into the mold cavity 44. This molten stream 61 first strikes step68 of block 5!] where it spreads as diagrammatically illustrated inFigs. 16 and 17. The fanned out stream then strikes the inclined innerwall of sprue passage 48 and enters the mold cavity as a ribbon-likestream to impinge at an angle to the rail head. The major portion of themetal which first enters the mold cavity forces its way around the end66 of the conductor into overflow cavity 41 so that the body-of metalwhich forms the terminal finds the rail head, conductor end, and moldcavity well heated upon. arrival and a homogeneous weld is producedwithout the occurrence of cold shot metal or incomplete coverage. Aconductor of the type illustrated will desirably be employed having arecurved end adapted to terminate centrally of the entrance to theoverflow cavity so that the metal passing into such overflow chambermust flow past the end of the conductor. After the casting of theterminal, block 50 is slid up into dotted line position and clamp 4|released and elevated to dotted line position (Fig. 12). The mold blockis then withdrawn by a short horizontal movement to the right as viewedin such figure, leaving a terminal substantially as illustrated in Fig.15. Some slag 69 Will usually have accumulated above the metal and mayeasily be removed by a blow from a chisel. The stud 70 of overflow metalmay be detached from the body H of the terminal by nicking the sameclosely adjacent the point of'juncture and giving it a sharp rap with ahammer.

It will be seen from the foregoing that apparatus has thus been providedwhich is quickly and conveniently applicable even in restricted placesand which enables the employment of a method whereby a firm and solid.terminal is obtained without danger of gougingjor overheating the railhead. Various other advantages are fully apparent from the abovedescription.

Referring now to Figs. 19 to .23 inclusive, the crucible employed in theapparatus assembly of this invention may be further modified as thereinillustrated. Such crucible may be mounted on the bridge 6| as iscrucible 55 and comprises a bottom portion 12 with a sprue opening ortap hole I3 and an upper portion separable along a vertical line intotwo wall portions 14 and 15. Wall portion M is connected to the bottomportion of the crucible by a hinge 76 and to wall portion 15 by pins 11and I8 permitting relative lateral movement of such wall portions (seeFig. 22). A handle '19 is provided to facilitate manipula tion of thecrucible parts, and a metal band 88 attached to wall portion 14encircles the crucible and prevents withdrawal of portion 15 from thepins. A catch comprising a semi-circular groove 8! in portion 35 and anarm 82 pivotally mounted I on bottom portion 72 may be employed althoughnot absolutely necessary since relative movement of the component partsmay be made quite frictional.

In operation, the upper portion of the crucible I.

is pivoted as. a unit on hinge 16 and a metal slug or gate 83 placedover the sprue opening. The crucible is then closed (see Fig. 21) andcharged with the exothermic powder. Upon ignition of the powder thereaction takes place forming 'a mass of superheated metal which meltsthe slug and drops into the mold cavity. Alayer or shell of slag 84 isleft in the crucible which would be difficult of removal if it were notfor the form of construction employed. The crucible is opened out asshown in Fig, 22, the slag shell removed, and a new slug placed over thesprue opening. It is much simpler to properly place such slug when thecrucible is thus divided along a'hori- "zont-al line adjacent its bottomthan when the slug must be dropped into a crucible and positioned bymeans of a rod, pencil, or the like. It has also been found that metalproduced in a crucible of this type forms a particularly homogeneous andnon-porous weld without the occlusion of nitrogen gas as otherwisesometimes occurs. This beneficial effect i apparently due to the ventingof gases during the reaction through the narrow passage left between thebottom portion and upper portion of the crucible as indicated by stainstherein. The same benefit does not accrue when the crucible is merelysplit along a vertical line. Since the crucible tapers inwardlytowardthe upper opening or neck undue spat tering is avoided during the ratherviolent reaction. When hinged directly to the mold block as by hinge 85in the manner indicated in Fig. 23, the device may be operated in amanner generally similar to that of Figs. 1-7, the crucible being tippedback to permit the raising of movable block 50. It is then tipped back,opened up, the slag shell removed and a new slug placed in position.Obviously such crucible, while particularly desirable as a componentpart of the app'aratus of this invention, is adapted for use generallywhere similar problems are encountered.

Other modes of applying the principle of my invention may be employedinstead of the one explained, change being made as regards the mechanismherein disclosed, provided the means stated by any of the followingclaims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A mold for cast Welding the end of a rail bond conductor to a railcomprising a block of refractory material having a main cavity in oneface thereof wherein the bond terminal is adapted to be cast and anothercavity extending to an adjacent side of said block adapted to closelyfit the body of the bond with the end of the latter extending into suchmain cavity, a sprue passage leading from the upper portion of saidblock to said main cavity, at least a portion of said passage being opento the rail contacting face of said block, and a movable memberoperative to enclose such open portion of said passage.

2. A mold for cast welding the end of a rail bond conductor to a railcomprising a block of refractory material having a main cavity intoneface thereof wherein the bond terminal is adapted to be cast and anothercavity extending to an adjacent side of said block adapted to closelyfit the body of the bond with the end of the latter extending into suchmain cavity, a sprue passage leading from the upper portion of saidblock to said main cavity, at least a portion of said passage being opento the rail contacting face of said block, and a movable memberoperative to enclose such open portion of said passage, said memberbeing swingably connected with said block.

3. A mold for cast welding the end of a rail bond conductor to a railcomprising a block of refractory material having a main cavity in oneface thereof wherein the bond terminal is adapted to be cast and anothercavity extending to an adjacent side of said block adapted to closelyfit the body of the bond with the end of the latter extending into suchmain cavity, a sprue passage leading from the upper portion of saidblock to said main cavity, at least a portion of said pas sage beingopen to the rail contacting face of said block, and a movable memberoperative to enclose such open portion of said passage, said memberbeing hingedly connected with said block about a horizontal axis.

4. A mold for cast welding the end of a rail bond to a rail, said moldcomprising a block of refractory material having a recessed faceconforming to the face of the rail to which the bond is to be attached,the recess in such mold face comprising a main cavity wherein theterminal is cast, and a smaller cavity extending to an adjacent end ofthe mold adapted to closely fit the body of the bond with its endextending into such main cavity, a sprue passage leading from above tosaid cavity, and a movable block adapted in one position to laterallyclose a portion of such passage and in another position to leave thesame exposed.

5. A mold for cast welding the end of a rail bond to a rail, said moldcomprising a block of refractory material having a recessed faceconforming to the face of the rail to which the bond is to be attached,the recess in such mold face comprising a main cavity wherein theterminal is cast and-a smaller cavity extending to an adjacent end ofthe mold adapted to closely fit the body ofthe bond with its endextending into such main cavity, a sprue passage leading from above tosaid cavity, and a movable block swingably attached to said mold adaptedin one position to laterally close a portion of such passage and inanother position to leave the same exposed.

6. A mold for cast welding the end of a rail bond to a rail, said moldcomprising a block of refractory material having a recessed faceconforming to the face of the rail to which the bond is to be attached,the recess in such mold face comprising a main cavity wherein theterminal is cast and a smaller cavity extending to an ad jacent end ofthe mold adapted to closely fit the body of the bond with its endextending into such main cavity, a sprue passage leading from above tosaid cavity, a movable block adapted in one position to laterally closea portion of such passage, and a resilient member swingably connectingsaid block with said mold, whereby. such passage may be exposed.

7. A device for cast welding a rail bond conductor to a rail comprisinga mold with. an open cavity in its rail-engaging face adapted to hold anend of said conductor, a sprue opening to said mold cavity, said sprueopening also beingopen tothe rail-engaging face of said mold, a cruciblehingedly mounted above said sprue opening and communicating therewith bymeans of a hole in the bottom of said crucible, a slidable block closingthe open side of said sprue opening, and clamping means whereby the openface of said mold may be held in engagement with the side of the railhead.

8. A device for cast welding a rail bond conductor to a rail comprisinga mold with an open cavity in its rail-engaging face adapted to hold anend of said conductor, a sprue opening leading to said cavity, a furthercavity at the back of said mold cavity proper and a small hole leadingfrom said further cavity to the exterior of the mold block, a cruciblehingedly mounted above said sprue opening and communicating therewith bymeans of a hole in the bottom of said crucible, a slidable block closingthe open side of said sprue opening, and clamping means whereby the openface of said mold may be held in engagement with the side of said railhead.

9. A device for cast Welding a rail bond conductor to a rail comprisinga mold with an open cavity in its rail-engaging face adapted to hold anend of said conductor, a sprue opening leading to said cavity, saidsprue opening also being open to the rail-engaging face of said mold, afurther cavity at the back of said mold cavity proper and separatedtherefrom by a thin graphite disk with a hole in its center, a smallhole leading from the extremity of said further cavity to the exteriorof the mold block, a crucible hingedly mounted above said sprue openingand communicating therewith by means of a hole in the bottom of saidcrucible, a slidable block closing the open side of said sprue opening,and clamping means whereby the open face of said mold may be held inengagement with the side of said rail head.

10. A device for cast welding a rail bond conductor to a rail comprisinga mold with an open cavity in its rail-engaging face adapted to hold anend of said conductor, a sprue opening leading to said cavity, a furthercavity at the back of said mold cavity proper and separated therefrom bya thin graphite disk with a hole in its center, a small hole leadingfrom the extremity of said further cavity to'the exterior of the moldblock, and'clamping' means whereby the open face ofsaid mold may beheldin engagement with the side of saidrail head. 1

11. A mold assembly for. cast welding the end of a rail bond conductorto a rail comprising complementary elements of refractory material,one'of such elements having a main cavity'in that portion of itsprincipal face .adapted to engage the rail wherein the bonditerminal isadapted to be cast, the other of said complementary. elements .beingincontact with anotherportion of such principal face of said first-namedelement and defining therewith a sprue lopening leading upward in saidassembly from said main cavity. 12. A m'oldiassembly. for cast weldingthe end of a rail bond conductor to a rail comprising complementaryelements'of refractory material, one of such elements having a.maincavity in that portion of its principal face-adapted? to engage the railwherein the bond terminal is adapted to be cast, the other I o'f saidcomplementary elements beingremovablyheld in contact with anotherportion of such principal-face ofsaid first-named element anddefiningtherewith a sprue openingleading upward from said main cavity; Y1 I 13. In combination, a device for cast'welding a rail bond conductorto a'r'a'il comprising a mold with a cavity in its rail-engaging faceadapted to hold an end of such conductor, a

sprue opening leading to such cavity, a further cavity communicatingwith such first-named v cavity and adapted to receive weld metal inexcess of that required for thebond terminal; said cavities being sodisposed that an end of such rail bond conductor held in saidfirst-named cavity will block a portion of the entrance to said furthercavity, and clamping means whereby to hold said mold in engagement withthe rail.

14. In combination, a mold comprising a block of refractory materialhaving a rail engaging face, a main cavity in such face wherein the bondterminal is adapted to be cast, a smaller cavity extending to anadjacent end of the mold block adapted to closely fit the body of a bondwith the end of such bond extending into said main cavity, a spruepassage leading from above to said main cavity; and a crucible adaptedto communicate at its lower end with said sprue passage, said cruciblebeing separable into nent parts.

15. In combination, a mold comprising a block of refractory materialhaving a rail engaging face, a main cavity in such face wherein the bondterminal is adapted to be cast, a smaller cavity extending to anadjacent end of the mold block adapted to closely fit the body of a bondwith the end of such bond extending into said main cavity, a spruepassage leading from above to said main cavity; and a crucible adaptedto communicats at its lower end with said sprue passage, said cruciblebeing vertically separable into two component parts.

16. A mold for cast welding a rail bond conductor to a rail comprising ablock of refractory material with a cavity in its rail-engaging faceadapted to hold an end of such conductor, a movable block in one stationabutting against the face of said first-named block above such cavity,and a sprue passage leading upwardly from such cavity partly in saidfirst-named block and partly in said movable block.

17. A mold for cast Welding a rail bond contwo compoductor to a railcomprising a block of refractory material with a cavity in itsrail-engaging face adapted to hold an end of such conductor, a movableblock in one station abutting against the face of said first-named blockabove such cavity, a sprue passage leading upwardly from such cavitypartly in said first-named block and partly in said movable block, andinclined faces in said passage adapted to spread a stream of moltenmetal passing therethrough.

18.'A mold" for cast welding a rail bond condoctor to a rail comprisinga block of refractory material with a cavity in its rail-engaging faceadapted to hold an end of such conductor, a movable block in one stationabutting against the face of said first-named block above such cavity, asprue passage leading upwardly from such cavity partly in saidfirst-named block and partly in said movable block, and inclined facesin said passage adapted to spread a stream of molten metal passingtherethrough and cause such spread stream of metal to impinge againstthe surface of the rail at an angle thereto.

19. A crucible for use with exothermic reactions having a sprue openingin the bottom thereof, said crucible comprising two complementaryportions together defining a cavity having walls tapering inwardlytoward the upper opening of said crucible, said complementary portionsbeing separable along a substantially vertical line passing through suchsprue opening.

20. In combination, amcld comprising a block of refractory materialhaving a rail engaging face, a main cavity in such face wherein the bondterminal is adapted to be cast, a smaller cavity extending to anadjacent end of the mold block adapted to closely fit the body of a bondwith the end of such bond extending into said main cavity, a spruepassage leading from above to said main cavity; and a crucible having asprue opening at its lower end positioned to communicate with said firstnamed sprue passage, said crucible being vertically separable into twocomponent parts along a line passing through such sprue opening in thelower end thereof.

21. A device for cast welding a rail bond conduotor to a rail comprisinga mold block with an open cavity in its rail-engaging face adapted tohold an end of said conductor, a movable block in contact with the faceof said mold block above said cavity and defining therewith a sprueopening leading upward from said cavity, a crucible mounted above saidmold block and communieating with said sprue opening by means of a holein the bottom of said crucible, and clamping means operative to hold theopen face of said mold in engagement with the side of the rail.

CHARLES A. CADWELL.

